Experimental study of the pre-nonlinearity, nonlinearity and post-nonlinearity stages at medium wavelengths

Detecting nonlinearity in experimental data

The technique of surrogate data has been used as a method to test for membership of particular classes of linear systems. We suggest an obvious extension of this to classes of nonlinear parametric models and demonstrate our methods with respiratory data from sleeping human infants. Although our data are clearly distinct from the different classes of linear systems we are unable to distinguish b...

Forward model nonlinearity versus inverse model nonlinearity.

The issue of concern is the impact of forward model nonlinearity on the nonlinearity of the inverse model. The question posed is, "Does increased nonlinearity in the head solution (forward model) always result in increased nonlinearity in the inverse solution (estimation of hydraulic conductivity)?" It is shown that the two nonlinearities are separate, and it is not universally true that increa...

A Multilevel Nonlinearity Study

| Multilevel models are designed to deal with studies on data that contain hierarchical structures and are becoming increasingly important in many elds of research. Since they are limited to parametric models, in practice only linear multilevel models are used. We present a nonlinear multilevel approach to investigate nonlinearity in relations. This model is based on nonlinear feed-forward netw...

Nonlinearity In Exchange Rates and Forecasting

Nonlinearity pdf